Abstract The goal of this fast-track SBIR proposal is to increase patient adherence to SBIRT-related recommendations given to patients by a primary care provider (PCP). The success of SBIRT (Screening, Brief Intervention, and Referral to Treatment) in the primary care setting has been inconsistent in terms of patients following through on treatment referral recommendations, with averages as low as 10%. For a variety of reasons, many patients, irrespective of their specific disease, do not adhere well to clinical recommendations. One way to improve adherence has been to personalize the recommendations for each individual?s needs, especially using digital technology, such as apps. The aim of NIDA to develop a sophisticated smart phone based tool for improving patient follow up to SBIRT recommendations is therefore well justified. CHESS Health has already developed an automated digital tool (eIntervention) with key elements requested by this RFA. eIntervention is designed to encourage patient adherence to PCP recommendations following SBIRT. Using a variety of the RFA required functionalities, eIntervention is designed to facilitate and motivate each patient to enter treatment, once that patient has been identified by SBIRT as having a substance use disorder (SUD) or as being at risk of such. eIntervention is commercially available and was developed in response to customer requests. However, eIntervention does not contain all of the functionalities requested by NIDA in this RFA and we do not have data to validate efficacy. Such validation is important for supporting wide spread dissemination. We propose to enhance our existing eIntervention solution with new functionalities that address the requirements set forth in this RFA and carry out a randomized study of efficacy. In Phase I, our Specific Aim is to evaluate feasibility of our program for improving adherence to SBIRT recommendations to patients from PCPs. This Specific Aim will be accomplished in two Tasks: Task 1: Add functionality to our prototype that address most requirements outlined in the RFA. Task 2: Demonstrate acceptability, feasibility, and preliminary efficacy of the prototype eIntervention in improving patient linkage to and engagement in indicated follow-up specialty SUD care. If shown to be feasible, in Phase II, our Specific Aim is to evaluate a near commercial quality product that contains all of the features required by the RFA. The Specific Aim will be accomplished in two Tasks: Task 1: Modifications to the program (months 1-3). Task 2: The randomized clinical trial to test efficacy of SBIRT/eIntervention compared to SBIRT/TAU. Criteria for Success: We aim to double the current rate of follow-up specialty SUD care (e.g. go from ~17% to an achieved rate of ~35%), a highly impactful effect. All patients, including those identified as at risk, must show a reduction in substance use. Patients and PCPs must rank the program with an average of 3.5 on a five-point Likert scale for usability, satisfaction, and willingness to use with the program again.